This disclosure relates to a block fitting for a vehicular air conditioning system that includes a rigid primary seal for the refrigerant conduit and a second, polymeric seal, spaced from the primary seal. More particularly, it relates to such a block fitting wherein the seals are pre-assembled in place to one block for creating a fluid tight seal on joinder of the blocks.
Vehicular air conditioning systems contain one of a variety of environmentally acceptable refrigerants. Concerns about the release of refrigerants into the atmosphere have led to regulations that mandate operation of refrigeration systems with substantially no leaks. The tubes that make up the piping in these systems may be connected to one another at certain junctions using a block fitting. To connect opposing tubes, for example, each tube is attached to a respective element of the block fitting, and the two blocks are then connected to one another. The joint is sealed by a primary seal member of deformable metal or other suitable material. Often a secondary polymeric seal is also provided within the fitting joint. Typically, vehicular air conditioning systems include components from several sources assembled by the OEM. It is common for one block of a block fitting to be integral with a major system component such as a compressor or condenser and the mating fitting element part of the line set. Modern assembly procedures mandate simplified component delivery and handling. An enhancement provided in this disclosure is that the interposed seals accompany one of the blocks as a pre-assembled sub-assembly. Such an approach eliminates separate processing of seal components, thereby improving productivity.